Endless cleaning web



y 12, 1970 H. o. STOEVER ETAL 3,510,903

ENDLES S CLEANING WEB Filed May 1, 1968 DEVELOPER STATION FIG.I

FIG.2

HANS O. STOEVER STEPHEN F. MICHATEK INVENTORS A2 @444 ATTORNEYS UnitedStates Patent 3,510,903 ENDLESS CLEANING WEB Hans O. Stoever and StephenF. Michatek, Rochester,

N.Y., assignors to Eastman Kodak Company, Rochester, N .Y., acorporation of New Jersey Filed May 1, 1968, Ser. No. 725,742 Int. Cl.A471 25/08; B41f 35/00; G03g 1/22 U.S. Cl. 15-256.5 Claims ABSTRACT OFTHE DISCLOSURE Residual toner particles on a photoconductive belt arecleaned therefrom by frictional engagement of a cleaning web runningalong an endless path in the opposite direction to the belt. Thecleaning web itself is cleaned by a vacuum so that it may be reused.

BACKGROUND OF THE INVENTION Field of the invention This inventionrelates to a device for cleaning residual toner particles from aphotoconductive surface, and more particularly a web, movable along anendless path, for cleaning a flexible photoconductive member. The web inturn is cleaned, as by a vacuum cleaning device.

Description of the prior art In a conventional electrophotographicapparatus, an electrostatic image is formed on a photoconductivesurface. This image is then toned by a suitable developing material,such as a dry toner powder. The developed toner image is thentransferred to a receiver. However, a small amount of residual tonerwill remain On the photoconductive surface which must be removedtherefrom prior to the forming and transfer of subsequent images toprevent ghost images from being formed during subsequent transfers.Various attempts have been made to clean photoconductive surfaces. Oneis by means of a rotating brush. Brushes are usually made from fur ofsuch animals as beaver, fox and rabbit and hence are relativelyexpensive. Also, brush cleaning can create a cloud of toner particles,as they are brushed from the photoconductor, which may settle on otherparts of the machinery.

Another known method of cleaning a photoconductive surface is by the useof a web of material fed from a supply spool to a takeup spool with anintermediate portion thereof being brought into frictional engagementwith the photoconductive material for cleaning. With this system,

the used web material must be replaced periodically with a clean roll ofcleaning material. Unfortunately, the cleaning web may run out at acritical time, such as in the middle of a printing operation, requiringshut down of the machine at an inopportune time. If the web is changedwhen the machine is normally not in use, chances are that it will bechanged before all of the cleaning web has been used, resulting in theloss of some unused material.

Another prior art device utilizes an endless web for recirculating tonerfrom the photoconductor to the toning station.

SUMMARY OF THE INVENTION In accordance with this invention, a web,movable along an endless path, is provided which frictionally contacts aphotoconductive surface to remove residual toner particles therefromwhich are collected on the web. The web is then cleaned by a vacuumdevice which pulls air therethrough removing toner particles thereon.Thus, the Web may be used over and over again without replace'- ment fora substantial period of time. When replacement is necessary, it may bemade when the machine is noranally shut down. In addition, the web maybe made of 3,510,903 Patented May 12, 1970 ice any suitable low-costpervious material, such as cheese cloth, terry cloth or other clothhaving a close weave. The cleaning web may be brought in contact withthe photoconductive surface along a line contact, over an extendedsurface or on a curved surface, as required.

Additional features of this invention will become ap parent from thedescription which follows taken in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERREDEMBODIMENTS In accordance with this invention, an electrographicmechanism M includes an endless photoconductive belt 10 which extendsaround spaced rollers 11 and 12 and may be driven by motor 13 through adrive belt 14. As is conventional in the art, photoconductive belt 10may comprise an outer photoconductive surface on a conductive backing.The photoconductive belt is driven past a charging station 15, andexposure station 16, a developing station 17, a transfer station 18 anda novel web cleaning device D.

Cleaning device D includes a cleaning web movable along an endless path,such as endless cleaning web 19, which may be made of close wovenpervious cloth material passing around a drive roller 21 and a series ofpressure rollers 22 to bring a substantial area of the web into planarcontact with photoconductive belt 10. A platen 23 is provided on theopposite side of photoconductive belt 10 to hold the belt in frictionalcontact with cleaning web 19. Advantageously, the cleaning web is drivenin a direction opposite that of photoconductor 10. A shroud or housing24 extends around a substantial portion of cleaning web 19, as shown,which is provided with an air inlet 25 and an air outlet 26 to which avacuum may be applied to provide air moving means for cleaning tonerparticles from the web. Conveniently, inlet 25 is on the inside of thecleaning web and outlet 26 is on the outside of the web so that air ispulled through web 19 causing toner particles to be removed from the webso that it may be used over and over again to clean photoconductive belt10. Thus, there is no necessity to frequently change the cleaning webnor will a long printing cycle need to be interrupted so that the webmay be changed.

An alternative electrographic mechanism M. is shown in FIG. 2 whereinphotoconductive belt 10' moves past a web cleaning device D'. In thisdevice, a cleaning web 27 extends around a pressure roller 28 and adrive roller 29. The portion of cleaning web 27 which extends aroundpressure roller 28 is brought into line contact with photoconductivebelt 10' which is held in frictional engagement with the cleaning web bya platen 23'. A shroud or housing 31 extends around Web 27 and isprovided with an inlet 32 on the inside of web 27 and an outlet 33 onthe outside of the web which is connected to a. vacuum for pulling airthrough the web to clean toner particles therefrom so that it may beused over a long period of time.

In the embodiment of FIG. 3, the photoconductive belt 10" ofelectrophotographic mechanism M is cleaned in the vicinity of roller 11"which serves as a platen to hold the photoconductor in frictionalengagement with an endless cleaning web 34 which extends around a driveroller 35 and a pair of pressure rollers 36 and 37 as shown. Theserollers serve to hold the cleaning web against the photoconductive beltover a substantial portion of the circumference of roller 11. A shroud38 extends around the belt and is provided with an inlet 39 on theinside of the belt and an outlet 40 on the outside thereof which isattached to a vacuum so that air may be pulled through the web to cleantoner particles therefrom which have been cleaned from thephotoconductor.

From the foregoing, the advantages of this invention are readilyapparent. A cleaning device has been provided l so that it may be usedover and over again. In the embodiment of FIG. 1, the web engages thephotoconductor over a substantial area and is backed up by a relativelyfiat platen. In the embodiment of FIG. 2 line contact is made betweenthe cleaning web and photoconductor, the latter being backed up bysubstantially planar platen. In FIG. 3,

the cleaning web passes over a substantial portion ofthe photoconductorwherein a large roller serves as a backup platen.

The invention has been described in considerable detail with referenceto preferred embodiments thereof, but it will be understood thatvariations and modifications can be effected within the spirit and scopeof the invention.

What is claimed is:

1. A cleaning device for cleaning residual toner particles from aphotoconductive surface, said device comprising:

a pervious cleaning web having an inside surface and an outside surface;means for moving said cleaning web means for urging the outside surfaceof said cleaning Web into frictional rubbing contact with saidphotoconductive surface for cleaning the residual toner particles fromsaid surface and collecting them on said cleaning web; and

means for moving air through said cleaning web to remove said residualtoner particles therefrom.

2. A cleaning device, as claimed in claim 1, wherein said urging meansbrings 'said cleaning web into frictional engagement with saidphotoconductive surface along a line contact.

3. A cleaning device, as claimed in claim 1, wherein:

said urging means brings said web into frictional engagement withsaidphotoconductive surface over a substantial area.

4. A cleaning device, as claimed in claim 3, wherein:

said urging means brings said cleaning web into contact with saidphotoconductive surface over a substantially planar area.

along an endless 5. A cleaning device, as claimed in claim 3, wherein:

said urging means brings said cleaning web into contact with saidphotoconductive surface over a substantially arcuate area.

6. A cleaning device, as claimed in claim 1, further including:

a backup platen for holding the photoconductive surface in frictionalengagement with said cleaning web.

7. A cleaning device, as claimed in claim 6, wherein said platen isplanar.

8. A cleaning device, as claimed in claim 6, wherein said platen is aroller.

9. A cleaning device for cleaning residual toner particles from aphotoconductive belt, said device including:

an endless cleaning belt;

drive means for moving said endless belt through an endless path;

means for urging said cleaning web into frictional contact with saidphotoconductive belt for cleaning said toner particles therefrom andcollecting them on said cleaning web;

a shroud substantially surrounding said cleaning web and having an inleton one side of said web and an outlet on the other side of said web,said outlet being connectable to a vacuum producing means so that airmay be drawn in through said inlet and through said cleaning web so thatresidual toner particles thereon will be removed therefrom and carriedthrough said outlet.

10. A cleaning device as claimed in claim 1 wherein said air movingmeans includes:

a shroud substantially surrounding a portion of said cleaning web to becleaned, said shroud having air inlet means adjacent the inside of saidcleaning web and having air outlet means adjacent the outside of saidcleaning web so that means may be applied to said shroud to move air insaid inlet and through said web and out said outlet to dislodge tonerparticles from said web to be removed through said outlet by said movingair.

References Cited UNITED STATES PATENTS 3,298,904 1/1967 Le Compte 134-15X 3,074,086 1/1963 Remer 15-1.5 3,411,932 11/1968 Malone et a1 151.5 X2,832,977 5/1958 Walkup et a1. 15--1.5

FOREIGN PATENTS 319,208 3/ 1926 Germany. 137,012 7/1959 U.S.S.R.

WALTER A. 'SCHEEL, Primary Examiner L. G. MACHLIN, Assistant ExaminerUS. 01. X.R. 355-15

